
public abstract class Plus extends Operator {
	
	public double calcul(double aux1, double aux2){
		return aux1 + aux2;
	}
	public static double Calcul(double aux1,double aux2){
		return aux1 + aux2;
	}
	public double calculDerivata(){
		if(fStang==null || fDrept==null)
			System.exit(1);
		return calcul(fStang.calculDerivata(), fDrept.calculDerivata());
	}
	public String derivare(){
		if (fStang==null || fDrept==null)
			System.exit(1);
	
		return concatTermeni(fStang.derivare(), fDrept.derivare());
	}
	public String concatTermeni(String aux1, String aux2){
		String aux;
			if (aux1.compareTo("0") == 0 || aux2.compareTo("0") == 0)
				//if (!strcmp(aux1, "0") && !strcmp(aux2, "0"))
				aux = aux1;
			else if (aux1.compareTo("0") == 0) aux = aux2;
			else if (aux2.compareTo("0") == 0 ) aux = aux1;
			else
				aux = aux1 + "+" + aux2;
	return aux;
	}
	public static String concatTermens(String aux1, String aux2){
		String aux;
		if (aux1.compareTo("0") == 0 || aux2.compareTo("0") == 0)
			//if (!strcmp(aux1, "0") && !strcmp(aux2, "0"))
			aux = aux1;
		else if (aux1.compareTo("0") == 0) aux = aux2;
		else if (aux2.compareTo("0") == 0 ) aux = aux1;
		else
			aux = aux1 + "+" + aux2;
	return aux;
	}
	
}
